Não informado. (1937). Plant inventory. Bureau of Plant Industry, Soils and Agricultural Engineering.
Chicago-Zitierstil (17. Ausg.)Não informado. Plant Inventory. Washington: Bureau of Plant Industry, Soils and Agricultural Engineering, 1937.
MLA-Zitierstil (8. Ausg.)Não informado. Plant Inventory. Bureau of Plant Industry, Soils and Agricultural Engineering, 1937.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.